What is the MAIN reason that the Archduchess Caroline and the Countess of Brandweiss enjoy the music Mozart plays on the harp?
A.They are reminded of the countryside of their native land.
B.They are surprised that such a young boy can play so well.
C.They are longing for the days when they lived a simple peasant life.
D.They are familiar with the melody because they have sung it many times.